1. Field of the Invention
The present invention relates to a chip antenna and a method for adjusting a frequency of the chip antenna. More particularly, the invention relates to a chip antenna used in mobile communication equipment for mobile communications and local area networks (LAN). The invention is also concerned with a method for for adjusting a frequency of the above type of chip antenna.
2. Related Art of the Present Invention
FIG. 10 is a side perspective view illustrating a conventional chip antenna. A chip antenna 50 is formed of a rectangular-prism insulator 51, a conductor 52, a magnetic member 53, and external connecting terminals 54a and 54b. The insulator 51 is formed by laminating insulating layers (not shown) made of an insulating powder, such as alumina or steatite. The conductor 52 is made of, for example, silver or silver-palladium, formed in the shape of a coil within the insulator 51. The magnetic member 53 is made of a magnetic powder, such as a ferrite powder, and is formed within the insulator 51 and the coil-like conductor 52. The external connecting terminals 54a and 54b are attached to leading ends (not shown) of the conductor 52 and burned after the insulator 51 is fired.
The above known type of chip antenna is miniaturized compared with a whip antenna, which is commonly used for mobile communications. Accordingly, this chip antenna is surface-mountable. The bandwidth of the chip antenna, on the other hand, is comparatively narrow. In the manufacturing process, therefore, a deviation of the resonant frequency from a predetermined value seriously reduces the gain of the chip antenna, thereby lowering the yield of the chip antenna.